CA1182238A - Anaerobic composition including a hydroxy (meth) acrylate and a polymerizable polymeric adduct with pendant double bonds - Google Patents
Anaerobic composition including a hydroxy (meth) acrylate and a polymerizable polymeric adduct with pendant double bondsInfo
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- CA1182238A CA1182238A CA000405437A CA405437A CA1182238A CA 1182238 A CA1182238 A CA 1182238A CA 000405437 A CA000405437 A CA 000405437A CA 405437 A CA405437 A CA 405437A CA 1182238 A CA1182238 A CA 1182238A
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- Prior art keywords
- acrylate
- monomer
- methacrylate
- anhydride
- polymer
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F290/00—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups
- C08F290/02—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups on to polymers modified by introduction of unsaturated end groups
- C08F290/04—Polymers provided for in subclasses C08C or C08F
- C08F290/046—Polymers of unsaturated carboxylic acids or derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J4/00—Adhesives based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; adhesives, based on monomers of macromolecular compounds of groups C09J183/00 - C09J183/16
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
POLYMERIC ADDUCTS WITH PENDANT POLYMERIZABLE DOUBLE BONDS, THEIR
PREPARATION AND USE AS REACTIVE THICKENERS IN IMPROVED
ANAEROBIC COMPOSITIONS
ABSTRACT OF THE DISCLOSURE
Novel stable anaerobic compositions are prepared which contains as a novel reactive thickener, a polymerizable polymeric adduct having pendant double bonds which is dissolved in a polymerizable monomeric diluent. The anderobic compositions show improved performance proper-ties. The thickener is prepared by reacting an anhydride-containing polymer with an excess of a C2-C5 hydroxyalkyl acrylate or meth-acrylate (e.g. hydroxyethyl and hydroxypropyl methacrylate), optionally in the presence of (meth)acrylate monomers which are not reactive with the anhydride groups of the polymer and which act as an additional diluent. The polymer may be prepared by conventional free radical polymerization techniques using maleic, citraconic, and/or itaconic anhydride and an ethylenically unsaturated monomer (e.g. C1-C10 alkyl acrylates or methacrylates or styrene).
PREPARATION AND USE AS REACTIVE THICKENERS IN IMPROVED
ANAEROBIC COMPOSITIONS
ABSTRACT OF THE DISCLOSURE
Novel stable anaerobic compositions are prepared which contains as a novel reactive thickener, a polymerizable polymeric adduct having pendant double bonds which is dissolved in a polymerizable monomeric diluent. The anderobic compositions show improved performance proper-ties. The thickener is prepared by reacting an anhydride-containing polymer with an excess of a C2-C5 hydroxyalkyl acrylate or meth-acrylate (e.g. hydroxyethyl and hydroxypropyl methacrylate), optionally in the presence of (meth)acrylate monomers which are not reactive with the anhydride groups of the polymer and which act as an additional diluent. The polymer may be prepared by conventional free radical polymerization techniques using maleic, citraconic, and/or itaconic anhydride and an ethylenically unsaturated monomer (e.g. C1-C10 alkyl acrylates or methacrylates or styrene).
Description
3~
POLYMERIC ADDUCTS WITH PENDANT POLYMERIZABLE DOUBLE BONDS, THEIR
PREPARATION AND USE AS REACTI~IE THICKENERS IN IMPROVED
ANAEROBIC COMPOSITIONS
This invention relates to novel anaerobic curing compositions con-taininy conventional polymerizable (meth)acrylate monomers, a free radical initiator, and a novel reactive thickener. It also relates to a process for preparing the thickener. It further relates to the use of the improved anaerobic compositions as adhesives and sealants.
Anaerobic compositions are well-known in the art. They are so formulated or treated that the compositions remain in an uncured state over long periods of ~ime provided that the compositions are exposed to an adequate supply of air or oxygen throughout that period, but which polymerize spontaneously upon the exclusion of air or oxygen therefrom, as when placed between non-porous surfaces (e.g. metal or glass).
Depending upon the exact formulation, such compositions may be used as adhesives or sealants.
It is known to incorporate as thickeners in anaerobic compositions inorganic compounds such as Cabosil (trade mark for a fumed silica sup-plied by the Cabot Corp~), tackifiers such as rosins~ rosin derivatives and terpenes, polymeric thickeners such as methacrylate and styrene-methacrylate polymers, and synthetic rubbers such as butadiene-styrene and butadiene-acrylonitrile. These thickeners do little to improve the final properties of the cured compositions since they do not take part
POLYMERIC ADDUCTS WITH PENDANT POLYMERIZABLE DOUBLE BONDS, THEIR
PREPARATION AND USE AS REACTI~IE THICKENERS IN IMPROVED
ANAEROBIC COMPOSITIONS
This invention relates to novel anaerobic curing compositions con-taininy conventional polymerizable (meth)acrylate monomers, a free radical initiator, and a novel reactive thickener. It also relates to a process for preparing the thickener. It further relates to the use of the improved anaerobic compositions as adhesives and sealants.
Anaerobic compositions are well-known in the art. They are so formulated or treated that the compositions remain in an uncured state over long periods of ~ime provided that the compositions are exposed to an adequate supply of air or oxygen throughout that period, but which polymerize spontaneously upon the exclusion of air or oxygen therefrom, as when placed between non-porous surfaces (e.g. metal or glass).
Depending upon the exact formulation, such compositions may be used as adhesives or sealants.
It is known to incorporate as thickeners in anaerobic compositions inorganic compounds such as Cabosil (trade mark for a fumed silica sup-plied by the Cabot Corp~), tackifiers such as rosins~ rosin derivatives and terpenes, polymeric thickeners such as methacrylate and styrene-methacrylate polymers, and synthetic rubbers such as butadiene-styrene and butadiene-acrylonitrile. These thickeners do little to improve the final properties of the cured compositions since they do not take part
2~
in the final cure but remain as a separate component in the cured adhesive or sealant.
The present invention provides novel and improved anaerobic compo-sitions, useful as adhesives and sealants, which have incorporated there-in, as a novel reactive thickener, a polymerizable polymeric adducthaving pendant double bonds which is dissolved in a polymerizable monomeric diluent~ It Further provides a method for the preparation of the thickener by reacting a polymer containing reactive anhydride groups with an excess of a hydroxy-containing (meth)acrylate monomerO
Novel stable anaerobic composi-tions are prepared which comprise a.) at least one polymerizable acrylate or methacrylate monomer;
b.) at least one reactive thickener; and c.) a free radical initiator in sufficient concentration to ini-tiate cure upon the exclusion of oxygen;
said reactive thickener comprising at least one polymerizable poly-meric adduct having pendant double bonds dissolved in a polymerizable monomeric diluent; said adduct being the addition reaction product of an anhydride-containing polymer and a hydroxy-containing monomer selected from the group consisting of a C2-C5 hydroxyalkyl acrylate, C2-C5 hydroxyalkyl methacrylate, and mixtures thereof; said polymer comprising about 005-50 mole ~ of an anhydride monomer selected from the group con-sisting of maleic anhydride, citraconic anhydride, itaconic anhydride, and mixtures thereof and about 50-99.5 mole % of a monomer having the formula CH2 ~ C(R1)X, wherein R1 is H, CH3, or CN and X is a phenyl or COOR group with R being a halogen substituted or unsubsti-tuted C1-C1o alkyl or a halog~n, alkoxy, or ester-substituted or unsubstituted C7-C20 aralkyl group, said hydroxy-containing monomer being present in an amount in excess o~ the number of moles required to react with said anhydride groups in sdid polymer dnd serving dS said polymeri~able rnonomeric diluent.
More particularly, an anaerobic composition, comprisi.nP-(A) about 5-95% by weight of d polymerizable, anaerobically curable C2-Cs hydroxyalkyl acrylate or metllacrylate monomer;
(B) about 5-95~ by weight of a polymerizable polymeric adduct hav-ing pendant double bonds as a reactive thickener; the adduct being the addition reaction product of the C2-Cs hydroxyalkyl acrylate or metll-acrylte monomer of (A) and an ahydride-containing polymer derived from about 0.5-50 mole % maleic, citraconic, or itaconic anhydride and about 50-99.5 mole X of a monomer having the formula CH2 = C(Rl)X, wherein Rl is H, CH3 or CN, X is a phenyl or COOR group, and R is a halogen substituted or unsubstituted Cl-Clo alkyl group or a halogen, alkoxy, or ester substituted or unsubstituted C7-Czo aralkyl group, the ad-duct being free of unreacted anhydride groups;
(C) 0-15% by weight of a carboxyl-containing monomer; and (D) a free radical initiator in sufficient concentration to ini-tiate cure upon the exclusion of oxygen.
The process for preparing the improved anaerobic composition herein comprises the step of adding thereto from about 5 to 95% by weight of a reactive thickener, based on the total composition weight; the reac-tive thickener being described hereinabove.
The anaerobic compositions are formulated by conventional methods using typical acrylate or methacrylate monomers or mixtures thereof, a free radical initiator, and preferably, but not necessarily, a stabili-zer, an accelerator, a chelator, and/or minor amounts of acidic mono-mers, such as acrylic acid, methacrylic acid, and/or citraconic, ita-conic, and maleic acid or their anhydrides.
32'~3~3 - 3a -The anaerobic coMpositions are useful as adhesives and sealants which, on curing, show improved performance properties. The properties of the cured composition depend on the glass transition temperature (Tg) of the backbone and the grafting polymer. For example, cured ddhesives having a low Tg (<0C) on the polymer backbone (e.g. ethyl acrylate copolymers) and high tg (>50C~ on the grafting polymer show improved impact and tensile shear strengths. Cured adhesives having a high Tg On both the backbone (e.~. styrene copolymers) and graftiny polymers show improved torque. The Tg f the polymer backbone can be conveniently modified by properly selecting the rnonomers used in the preparation of the polymer used for preparing the adduct.
The novel reactive thickener for anaerobic compositions comprises a polymerizable polymeric adduct having pendant double bonds with the adduct, described hereinabove, comprising recurring units of one or more of the formul dS:
CHz- C(R1)X--fH--C(R2)--- , or ~C(Rl)X--CH~--CH C(R2)--, or O--C C=O O=C C=O
O O O O
H R3- 0 -~CI- Cl_ CH2 H 0 R4 -CH2- C(Rl)X - CH - C(R2) - , or -C(Rl)X--CH2 - IcH C(R2) - , or O=C C `O O=C C=O
O O O O
H2C = C- C - 0 -R3 H H2C= C- C 0 -13 ll R4 8 R4 o - CH2 C(Rl~X CH2 --C(Rl)X--CH2--CH2 O ~ O
Il ~1 1 H- 0 -C- C-- , or H- 0- C- C- , or R4 o ¦ R4 0 H2C- C~ C- o - R3~o-1C- CH2 HzC = C- C - 0~ R3-o ICl CH2 o --CH2--C(Rl)X--CH2 --C(Rl)X CH2--CH2 R4 0 0 R4 o 0 H2C~rC ~ C - O - R3-0- C -( :- , or H2C = C- C- O- R3-o- C- C - ;
20H- 0- C-~CH2 H - 0- C- CH2 B 1l wherein Rl and X, are as defined hereinabove, R2 and R4 are indepen-dently H or CH3, and R3 is a C2-Cs alkyl group.
in the final cure but remain as a separate component in the cured adhesive or sealant.
The present invention provides novel and improved anaerobic compo-sitions, useful as adhesives and sealants, which have incorporated there-in, as a novel reactive thickener, a polymerizable polymeric adducthaving pendant double bonds which is dissolved in a polymerizable monomeric diluent~ It Further provides a method for the preparation of the thickener by reacting a polymer containing reactive anhydride groups with an excess of a hydroxy-containing (meth)acrylate monomerO
Novel stable anaerobic composi-tions are prepared which comprise a.) at least one polymerizable acrylate or methacrylate monomer;
b.) at least one reactive thickener; and c.) a free radical initiator in sufficient concentration to ini-tiate cure upon the exclusion of oxygen;
said reactive thickener comprising at least one polymerizable poly-meric adduct having pendant double bonds dissolved in a polymerizable monomeric diluent; said adduct being the addition reaction product of an anhydride-containing polymer and a hydroxy-containing monomer selected from the group consisting of a C2-C5 hydroxyalkyl acrylate, C2-C5 hydroxyalkyl methacrylate, and mixtures thereof; said polymer comprising about 005-50 mole ~ of an anhydride monomer selected from the group con-sisting of maleic anhydride, citraconic anhydride, itaconic anhydride, and mixtures thereof and about 50-99.5 mole % of a monomer having the formula CH2 ~ C(R1)X, wherein R1 is H, CH3, or CN and X is a phenyl or COOR group with R being a halogen substituted or unsubsti-tuted C1-C1o alkyl or a halog~n, alkoxy, or ester-substituted or unsubstituted C7-C20 aralkyl group, said hydroxy-containing monomer being present in an amount in excess o~ the number of moles required to react with said anhydride groups in sdid polymer dnd serving dS said polymeri~able rnonomeric diluent.
More particularly, an anaerobic composition, comprisi.nP-(A) about 5-95% by weight of d polymerizable, anaerobically curable C2-Cs hydroxyalkyl acrylate or metllacrylate monomer;
(B) about 5-95~ by weight of a polymerizable polymeric adduct hav-ing pendant double bonds as a reactive thickener; the adduct being the addition reaction product of the C2-Cs hydroxyalkyl acrylate or metll-acrylte monomer of (A) and an ahydride-containing polymer derived from about 0.5-50 mole % maleic, citraconic, or itaconic anhydride and about 50-99.5 mole X of a monomer having the formula CH2 = C(Rl)X, wherein Rl is H, CH3 or CN, X is a phenyl or COOR group, and R is a halogen substituted or unsubstituted Cl-Clo alkyl group or a halogen, alkoxy, or ester substituted or unsubstituted C7-Czo aralkyl group, the ad-duct being free of unreacted anhydride groups;
(C) 0-15% by weight of a carboxyl-containing monomer; and (D) a free radical initiator in sufficient concentration to ini-tiate cure upon the exclusion of oxygen.
The process for preparing the improved anaerobic composition herein comprises the step of adding thereto from about 5 to 95% by weight of a reactive thickener, based on the total composition weight; the reac-tive thickener being described hereinabove.
The anaerobic compositions are formulated by conventional methods using typical acrylate or methacrylate monomers or mixtures thereof, a free radical initiator, and preferably, but not necessarily, a stabili-zer, an accelerator, a chelator, and/or minor amounts of acidic mono-mers, such as acrylic acid, methacrylic acid, and/or citraconic, ita-conic, and maleic acid or their anhydrides.
32'~3~3 - 3a -The anaerobic coMpositions are useful as adhesives and sealants which, on curing, show improved performance properties. The properties of the cured composition depend on the glass transition temperature (Tg) of the backbone and the grafting polymer. For example, cured ddhesives having a low Tg (<0C) on the polymer backbone (e.g. ethyl acrylate copolymers) and high tg (>50C~ on the grafting polymer show improved impact and tensile shear strengths. Cured adhesives having a high Tg On both the backbone (e.~. styrene copolymers) and graftiny polymers show improved torque. The Tg f the polymer backbone can be conveniently modified by properly selecting the rnonomers used in the preparation of the polymer used for preparing the adduct.
The novel reactive thickener for anaerobic compositions comprises a polymerizable polymeric adduct having pendant double bonds with the adduct, described hereinabove, comprising recurring units of one or more of the formul dS:
CHz- C(R1)X--fH--C(R2)--- , or ~C(Rl)X--CH~--CH C(R2)--, or O--C C=O O=C C=O
O O O O
H R3- 0 -~CI- Cl_ CH2 H 0 R4 -CH2- C(Rl)X - CH - C(R2) - , or -C(Rl)X--CH2 - IcH C(R2) - , or O=C C `O O=C C=O
O O O O
H2C = C- C - 0 -R3 H H2C= C- C 0 -13 ll R4 8 R4 o - CH2 C(Rl~X CH2 --C(Rl)X--CH2--CH2 O ~ O
Il ~1 1 H- 0 -C- C-- , or H- 0- C- C- , or R4 o ¦ R4 0 H2C- C~ C- o - R3~o-1C- CH2 HzC = C- C - 0~ R3-o ICl CH2 o --CH2--C(Rl)X--CH2 --C(Rl)X CH2--CH2 R4 0 0 R4 o 0 H2C~rC ~ C - O - R3-0- C -( :- , or H2C = C- C- O- R3-o- C- C - ;
20H- 0- C-~CH2 H - 0- C- CH2 B 1l wherein Rl and X, are as defined hereinabove, R2 and R4 are indepen-dently H or CH3, and R3 is a C2-Cs alkyl group.
3~
It is prepared by reacting an anhydride-containing polymer, which is substantially free o-F unreacted monomer, with an excess of a hydroxy-containing rnonomer, based on the moles of anhydride in said polymer, said reaction being carried out at about 50 to 100C for a time sufficient to insure substantially complete reaction of al'l said anhydride groups and to form a polymeri~able polymeric adduct having pendant double bonds dissolved in said excess hydroxy-containing monomer as a polymerizable monomeric diluent; said polymer comprising about 50-99.5 mole % of a monomer having the formula CH2 _ C(R1)X, wherein R1 is H, CH3, or CN and X is a phenyl or COOR group with R
being a halogen substituted or unsubsti-tuted C1-C1o alkyl or a halo-gen, alkoxy, or ester substituted C7-C1o aralkyl group, and 50-O.S
mole % o~ an anhydride monomer se'lected from the group consisting of maleic anhydride, citraconic anhydride, itaconic anhydride and mixtures thereof; said hydroxy-containing monomer selected from the group consisting of a C2-C5 hydroxyalkyl acrylate, C2-C5 hydroxyalkyl methacrylate and mixtures thereof.
The reaction may be carried out in the presence of (meth)acrylate monomers which are not reactive with the polymer's anhydride group.
The excess hydro~y-containing monomer and the non-reactive (meth)-acrylate monomer, if any9 act as the polymerizable monomeric diluent.
The anhydride-containing polymer used in the preparation of the adduct should be substantially free of unreacted monomer. It may be prepared by conventional free radical polymerization techniques, such as solu-tion polymerization, using maleic, citraconic, and/or itaconic anhydrideand at least one ethylenically unsaturated monomer such as ethyl, butyl, or octyl (meth)acrylate or styrene.
Preparation of The Novel Reactive Thickener The anhydride-containing polymers useful in preparing the reactive thickener are themselves prepared by free radical polymerization using known polymerization techniques, such as bulk, emulsion, suspension, or preferably solution polymerization. From 0.5-50 mole %, preferably 1.5-25 mole %, of an anhydride monomer selected frorn -the group consist-ing of maleic anhydride, citraconic anhydride, itaconic anhydride, and mixtures thereof is reacted with 50-99.5 mole %, preferably 75-98.5 mole %, of at least one ethylenically unsaturatecl monomer having the formula CH2 C(R1)X, where R1 is H, C~13, or CN; X is a phenyl or COOR
group with R being a C1-C1o alkyl group, optionally substituted with halogen, or a C7-C20 aralkyl group, optionally substituted with halo-gen, alkoxy~ or es~er groups.
Typical ethylenically unsaturated monomers suitable for reaction with the anhydrides include, for example, ethyl acrylate, butyl acrylate, octyl acrylate, methyl methacrylate, ethyl methacrylate, styrene, Q~ -methyl styrene, and the like. Mixtures of ethylenically unsaturated monomers may also be used. A typical polymerization is carried out at 50 to 100C, in a nitrogen atmosphere using a free radical initiator, such as azoisobutylnitrileg and a solvent such as ethyl acetate. If substantial amounts of excess monomer are present, they are preferably removed, as by stripping, prior to the subsequent reaction to form the polymeric adduct. Typically such stripping will remove any solvent present, and additional solvent, if desired, may be added prior -to or during the reaction to form the adduct, The anhydride-containing polymer is then reacted with at least one hydroxy-containing acrylate or methacrylate monomer such as a C2-C5 hydroxyalkyl acrylate or methacrylate9 preferably hydroxyethyl acrylate, 3~
hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl meth-acrylate, and mixtures thereof. The monomer reacts with the polymer by adding to the anhydride through the monomer's hydroxyl group and thus forms a polymerizable polynneric adduct having pendant double bonds. The hydroxy-containing monomer is used in an excess of the molar amount re-quired9 based on the number of moles of anhydride in the polymer.
Typically from 2 to 50 moles of hydroxy-containing monomer are used~
The excess monomer acts as polymerizable monomeric diluent. In order to reduce the viscosity of the thickener, it may be desirable in some cases to carry out this addition reaction in the presence of a polymer-izable monomeric diluent which is not reactive with the anhydride groups of the polymer. If the thickener is to be used in an anaerobic composition, any of the monomers typically used in such compositions except those containing groups reactive with anhydride groups (i.e.
hydroxy groups) may be used as the optional diluent. For anaerobic compositions these include the monomers in the five classes to be described hereinafter, preferably ~hose from the lst class (e.gO
tetraethyleneglycol dimethacrylate) and those frorn the 5th class.
The resulting reactive thickener contains 5 to 95 ~O by weight of the adduct, based on the total weight of the thickener. Preferably it contains 50 to 75 % of the adduct. If stored prior to incorporation in the anaerobic composition or prior to use as a coating composition, it should be stored in the presence of oxygen or air. In order to improve the storage stability of the thickener it is preferable, but not neces-sary9 that the composition contain a stabilizer such as an inhibitor forfree radical polymerization. Such inhibitors will be described hereafter.
The adduct is characterized by recurring units having one or more of the formulas:
CH2 - C(Rl)X ~ CH C(R2) - , or C(R1)X- CH2 -CH - -C(R2)~ , or O~C C--O O C C O
O O O O
H R3- 0- lCI- Cl= CH2 H R3- 0~ C- IC -CH2 -CH2 - C(Rl)X ~ fH f(R2) - , or -C(R1)X- CH2 - CH - C(R2~ , O~C C=O O--C C=O
O O O O
10R4 o R4 lo when maleic and/or citraconic anhydride are used in the polymer preparation, or having one or more of the formulas:
--CH2 C(Rl)X--,CH2--C(Rl)X--CH2--CH2 O l O
Il l 11 1~ H- 0- C - C ~ , orH 0 - C~ C ~ , or R4 0 R4 o H2C=1--C~O--R3-o--c ~c ~H2 H2C=l--C--O--K3-o--~--CH2 - CH2 - C(Rl)X ~ CH2 - C(R1)X- CH2 -CH2 R4 o 0 ¦ R4 0 0 l 11 11 11 11 11 1 H2C_ C - C - O- R3-0~ C- C-t , or H2C _ C C- 0- R3-o -C- j-H~ 0- C- CH2 H- 0- C- CH2 O
3~
g when itaconic anhydride is used in the polymer preparation~ R1 and X
are as defined above; R2 and R4 are independently H or CH3; and R3 is a C2-C5 alkyl group.
Preparation of The Anaerobic Composit_on The monomers employed herein are anaerobically curable monomers having at least one polymerizable acryldte ester group.
The 1st class of monomers useful herein correspond to the general formula:
8 ~R5~ R5 H2C=C--C--O - --(CH2)m ~ C--C~CH
where R5 is H, CH3, C2H5, CH20H~ or CH2-0-C(=O)-C(R6)=CH2; R6 is H, Cl, CH3 or C2H5; R7 is H, OH, or O-C(=O)-C(R6)=CH2; m is 1-8, preferably 1-4; n is 1-20; and p is 0-1.
Monomers typical of this class irclude, for example, ethyleneglycol dimethylacrylate, ethyleneglycol diacrylate, polyethyleneglycol diacry-late, tetraethylenglycol dimethacrylate, diglycerol diacrylate, die-thy-leneglycol dim~thacrylate, pentaerythritol triacrylate, and other poly-ester diacrylates and dimethcacrylates. The above class of monomers is described in U. S. Pat. No. 3,043, 820 issued July lO, 1962 to R. H.
Krieble.
The 2nd class of monomers useful herein correspond to the general formul a:
2~ IR5 IR5 H2C_ C ~C--CH2 ICl O ~ R6- )n 1l- R7- h - ~-o - R6 )n - C
O O O
23~3 where R5 is H, Cl, CH3, or C2H5; R6 is a C2-C6 alkylene; R7 is (CH2)m~
o,m,p ~ , C - C , C = C , / ~C~ , or C = <
H H H CH~ ~l n is 1-4; and m is 0-8.
Monomers typical or this class include, for example, dimethylacrylate of bis(ethyleneglycol) adipate, dimethacrylate of bis(ethyleneglycol) maleate, dimethacrylate oF bis(diethyleneglycol) phthalate, dimethacry-late of bis(tetraethylenglycol) phthalate, dimethylacrylate of bis(tetra-ethyleneglycol) malonate, dimethacrylate of bis(tetraethyleneglycol) sebacate, dimethacrylate of bis(ethylenglycol) phthalate, dime-thacrylate of bisttetraethyleneglycol~ maleate, and the diacrylates and ~-chloro-acrylates curresponding to said dimethacrylates, and the like. The abovecldss of monomers is described in U. S~ Pat. No. 3,457,212 issued July 22, 1969 to Y. Fukuoka et al.
The 3rd class of monomers useful herein are isocyanate-hydroxy-acrylate or isocyanate-aminoacrylate reaction products which may be characterized as acrylate-terminated polyurethanes and polyureides or polyureas. These monomers correspond to the general formula:
r 1l A - X - G - NH - B
_ _ n where X is 0 or N(R5~; R5 is H or a Cl-C7 alkyl; A represents the organic residue of an active-hydrogen-containing acrylate ester wherein the active hydrogen has been removed, the ester being hydroxy- or amino-substituted on the alkyl portion thereof and the methyl, ethyl, and 22~
chlorine homologs thereoF; B is a mono- or polyvalent organic radical selected from the group consisting of alkyl, al~ylene, alkenyl, alkeny-lene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, alkaryl, alkarylene, poly(oxyalkylene), poly(carboalkoxyalkylen~), and heterocyclic radicals both substituted and unsubstituted, and n is 1-6.
Monomers typical of this class include for example, the reaction product of a mono- or polyisocyanate, (e.g., toluene diisocyanate or methylene bis-phenyl diisocyanate) with an acrylate ester containing a hydroxyl or amine group in the non-acrylate portion thereo-f, (e.g.
hydroxyethyl methacrylate). The above class of monomers is described in U.S. Pat. No. 3,425,988 issued Feb. 4, 1969 to J. W. ~orman et al.
The 4th class of monomers useful herein correspond to the acrylate diesters of bis-phenol-type compounds. These monomers correspond to the general formula:
CH2 _ C - C ( 0 ~ C - CH2 ~n ~
R8 R10 1 Rll C ~ O ( C~l2 - C ~ O )n C - C - CH2 where R8 j5 CH3, C2H5, COOH, or H; R9 is H, CH3, or C2H5, R10 is H, CH3, or OH; R1l is H, Cl, CH3, or C2H5; and n is 0-8.
Monomers typical of this class include, for example, dimethacrylate and diacrylate esters of 4,4'-bishydroxy-ethoxy-bisphenol A; dimeth-acrylate and diacrylate esters of bis,ohenol A; etc. These monomers are described in Japanese Pat. Publication 70-15,640 of ~. Orite, M. Natsume, and N. Shimada in 1970.
2~3 The 5th class of monomers consists of monofunctional acrylate and methacrylate esters and the hydroxy-, amido-, cyano-, chloro-, and silane-substituted derivatives thereof. Such monomers include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hy-droxypropyl methacrylate, butyl acrylate, n-octyl acrylate, 2-ethyl-hexyl acrylate, decyl methacrylate~ dodecyl me-thacrylate, cyclohexyl methacrylate, t-butyl methacrylate, acrylamide, N-methylolacrylamide, diactone acrylamide, N-t-butyl acrylamide, N-~-octyl acrylamide, N-butyoxyacrylamide, garnma methacryloxypropyl trimethoxysilane, 2-cyano-ethyl acrylate, 3-cyanopropyl acrylate, tetrahydrofurfuryl chloroacry-late, glycidyl acrylate, glycidyl methacrylate, and the like.
The monomers useful herein are seen to be anaerobically curable monomers having one or more polymerizable acrylate or substituted acrylate ester groups as a common, unifying characteristic. The pre-ferred monomers are those in the 1st and 5th classes above described.
In the production of anaerobic curing adhesive compositions charac-terized by exceptionally high bond strength in the resultant cured poly-mer, the particular monomer employed may be chosen so as to contain an alcoholic, carboxylic, or other relatively polar group substituted thereof. Examples of such polar groups in addition to the hydroxyl and carboxyl groups include amino, amido, cyano, mercapto, and halogen polar groups. Monomers containing hydroxyl groups and/or labile hydrogen atoms are preferred. Examples of suitable monomers include hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate7 diacetone acrylamide, 2-cyanoethyl acrylate, 2-chloroethyl acrylate> 2-hydroxy-3-chloropropyl methacrylate, (meth)acrylic acid, itaconic acid, citraconic acid, maleic acid, and the like. The hydroxy-containing monomers are used in amounts from about 5-95%1 preferably 25-50%, and the carboxyl-containing monorners in amounts from about 001-15%, preFerably 0.5-10%, both by weight based on the total composition weight.
For bes-t results in terms of adhesive activity, the monomers are pre-Ferably employed in a purified state. However, the monomers may be com-prised of commercial grades in which inhibitors, stabilizers, other addi-tives or impurities may be present, provided that the activity and/or stability of the adhesive is not reduced to unacceptable levels.
In the preparation of the anaerobic curing compositions herein, it 1n is possible to employ a mixture of acrylate ester monomers. There may also be utilized, in combination therewith, other non-acrylic, ethylen-ically unsaturated copolymerizable comonomers such as unsaturated hydrocarbons, unsaturated esters and ethers, vinyl esters, and the like. Typical optional comonomers include vinyl acetate, rnethyl vinyl ether, methyl vinyl ketone, poly(ethylene maleate), allyl alcohol, allyl aceta-te, 1-octene, styrene, etc. Preferably9 the total optional non-acrylic monomer(s) will constitute no more than 50% by weight of the monomeric composi-tion, and most preferably no more than 30%.
The anaerobic compositions herein are prepared using conventional techniques. Useful free radical initiators include hydrogen peroxide and peroxy compounds such as organic hydroperoxides (e.g. cumene, t~butyl, and methylethyl ketone hydroperoxides), peroxides (e~g.
benzoyl, cyclohexyl, and hydroxycyclohexyl peroxides), and peresters (e.g. t-butyl perbenzoate and t-butyl peracetate; diazosulfones together with o-benzoic sulfimide (saccharin); c~-amino sulfones (e.g. N-(o- or p-carboethoxyphenyl)-(p-tolylsulfonemethyl) arnine); or azo compounds (e.g. 2,2'-azobis(isobutyronitrile).
Alternatively, an accelera-tor system consis-ting of a N-subs~ituted sulfonamide (e.g. N-tosyl-p-toluene sulfonamide, N-mesyl-p-toluene sul-fonamide9 N-mesyl-benzene sulfonamide, N-mesyl-methane sulfonamide, or N-benzene sulfonamide) or of an organic cyclic sulfimide (e.g. o-benzoic sulfimide) together ~ith an aromatic tertiary amine (e.g~ N,N-dimethyl-p-toluidine, N,N-diethyl-p-toluidine, N,N dimethyaniline, or 3,~-dimethyl-N,N-dimethylaniline) may be used with composi-tions containing at least 25 ppm of active oxygen (see U5s~ Patc No. 4,215,209 issued Jul. 29, 19~0 to D~ K. Ray-Chaudhuri et al. and U.S. Pat. No.
It is prepared by reacting an anhydride-containing polymer, which is substantially free o-F unreacted monomer, with an excess of a hydroxy-containing rnonomer, based on the moles of anhydride in said polymer, said reaction being carried out at about 50 to 100C for a time sufficient to insure substantially complete reaction of al'l said anhydride groups and to form a polymeri~able polymeric adduct having pendant double bonds dissolved in said excess hydroxy-containing monomer as a polymerizable monomeric diluent; said polymer comprising about 50-99.5 mole % of a monomer having the formula CH2 _ C(R1)X, wherein R1 is H, CH3, or CN and X is a phenyl or COOR group with R
being a halogen substituted or unsubsti-tuted C1-C1o alkyl or a halo-gen, alkoxy, or ester substituted C7-C1o aralkyl group, and 50-O.S
mole % o~ an anhydride monomer se'lected from the group consisting of maleic anhydride, citraconic anhydride, itaconic anhydride and mixtures thereof; said hydroxy-containing monomer selected from the group consisting of a C2-C5 hydroxyalkyl acrylate, C2-C5 hydroxyalkyl methacrylate and mixtures thereof.
The reaction may be carried out in the presence of (meth)acrylate monomers which are not reactive with the polymer's anhydride group.
The excess hydro~y-containing monomer and the non-reactive (meth)-acrylate monomer, if any9 act as the polymerizable monomeric diluent.
The anhydride-containing polymer used in the preparation of the adduct should be substantially free of unreacted monomer. It may be prepared by conventional free radical polymerization techniques, such as solu-tion polymerization, using maleic, citraconic, and/or itaconic anhydrideand at least one ethylenically unsaturated monomer such as ethyl, butyl, or octyl (meth)acrylate or styrene.
Preparation of The Novel Reactive Thickener The anhydride-containing polymers useful in preparing the reactive thickener are themselves prepared by free radical polymerization using known polymerization techniques, such as bulk, emulsion, suspension, or preferably solution polymerization. From 0.5-50 mole %, preferably 1.5-25 mole %, of an anhydride monomer selected frorn -the group consist-ing of maleic anhydride, citraconic anhydride, itaconic anhydride, and mixtures thereof is reacted with 50-99.5 mole %, preferably 75-98.5 mole %, of at least one ethylenically unsaturatecl monomer having the formula CH2 C(R1)X, where R1 is H, C~13, or CN; X is a phenyl or COOR
group with R being a C1-C1o alkyl group, optionally substituted with halogen, or a C7-C20 aralkyl group, optionally substituted with halo-gen, alkoxy~ or es~er groups.
Typical ethylenically unsaturated monomers suitable for reaction with the anhydrides include, for example, ethyl acrylate, butyl acrylate, octyl acrylate, methyl methacrylate, ethyl methacrylate, styrene, Q~ -methyl styrene, and the like. Mixtures of ethylenically unsaturated monomers may also be used. A typical polymerization is carried out at 50 to 100C, in a nitrogen atmosphere using a free radical initiator, such as azoisobutylnitrileg and a solvent such as ethyl acetate. If substantial amounts of excess monomer are present, they are preferably removed, as by stripping, prior to the subsequent reaction to form the polymeric adduct. Typically such stripping will remove any solvent present, and additional solvent, if desired, may be added prior -to or during the reaction to form the adduct, The anhydride-containing polymer is then reacted with at least one hydroxy-containing acrylate or methacrylate monomer such as a C2-C5 hydroxyalkyl acrylate or methacrylate9 preferably hydroxyethyl acrylate, 3~
hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl meth-acrylate, and mixtures thereof. The monomer reacts with the polymer by adding to the anhydride through the monomer's hydroxyl group and thus forms a polymerizable polynneric adduct having pendant double bonds. The hydroxy-containing monomer is used in an excess of the molar amount re-quired9 based on the number of moles of anhydride in the polymer.
Typically from 2 to 50 moles of hydroxy-containing monomer are used~
The excess monomer acts as polymerizable monomeric diluent. In order to reduce the viscosity of the thickener, it may be desirable in some cases to carry out this addition reaction in the presence of a polymer-izable monomeric diluent which is not reactive with the anhydride groups of the polymer. If the thickener is to be used in an anaerobic composition, any of the monomers typically used in such compositions except those containing groups reactive with anhydride groups (i.e.
hydroxy groups) may be used as the optional diluent. For anaerobic compositions these include the monomers in the five classes to be described hereinafter, preferably ~hose from the lst class (e.gO
tetraethyleneglycol dimethacrylate) and those frorn the 5th class.
The resulting reactive thickener contains 5 to 95 ~O by weight of the adduct, based on the total weight of the thickener. Preferably it contains 50 to 75 % of the adduct. If stored prior to incorporation in the anaerobic composition or prior to use as a coating composition, it should be stored in the presence of oxygen or air. In order to improve the storage stability of the thickener it is preferable, but not neces-sary9 that the composition contain a stabilizer such as an inhibitor forfree radical polymerization. Such inhibitors will be described hereafter.
The adduct is characterized by recurring units having one or more of the formulas:
CH2 - C(Rl)X ~ CH C(R2) - , or C(R1)X- CH2 -CH - -C(R2)~ , or O~C C--O O C C O
O O O O
H R3- 0- lCI- Cl= CH2 H R3- 0~ C- IC -CH2 -CH2 - C(Rl)X ~ fH f(R2) - , or -C(R1)X- CH2 - CH - C(R2~ , O~C C=O O--C C=O
O O O O
10R4 o R4 lo when maleic and/or citraconic anhydride are used in the polymer preparation, or having one or more of the formulas:
--CH2 C(Rl)X--,CH2--C(Rl)X--CH2--CH2 O l O
Il l 11 1~ H- 0- C - C ~ , orH 0 - C~ C ~ , or R4 0 R4 o H2C=1--C~O--R3-o--c ~c ~H2 H2C=l--C--O--K3-o--~--CH2 - CH2 - C(Rl)X ~ CH2 - C(R1)X- CH2 -CH2 R4 o 0 ¦ R4 0 0 l 11 11 11 11 11 1 H2C_ C - C - O- R3-0~ C- C-t , or H2C _ C C- 0- R3-o -C- j-H~ 0- C- CH2 H- 0- C- CH2 O
3~
g when itaconic anhydride is used in the polymer preparation~ R1 and X
are as defined above; R2 and R4 are independently H or CH3; and R3 is a C2-C5 alkyl group.
Preparation of The Anaerobic Composit_on The monomers employed herein are anaerobically curable monomers having at least one polymerizable acryldte ester group.
The 1st class of monomers useful herein correspond to the general formula:
8 ~R5~ R5 H2C=C--C--O - --(CH2)m ~ C--C~CH
where R5 is H, CH3, C2H5, CH20H~ or CH2-0-C(=O)-C(R6)=CH2; R6 is H, Cl, CH3 or C2H5; R7 is H, OH, or O-C(=O)-C(R6)=CH2; m is 1-8, preferably 1-4; n is 1-20; and p is 0-1.
Monomers typical of this class irclude, for example, ethyleneglycol dimethylacrylate, ethyleneglycol diacrylate, polyethyleneglycol diacry-late, tetraethylenglycol dimethacrylate, diglycerol diacrylate, die-thy-leneglycol dim~thacrylate, pentaerythritol triacrylate, and other poly-ester diacrylates and dimethcacrylates. The above class of monomers is described in U. S. Pat. No. 3,043, 820 issued July lO, 1962 to R. H.
Krieble.
The 2nd class of monomers useful herein correspond to the general formul a:
2~ IR5 IR5 H2C_ C ~C--CH2 ICl O ~ R6- )n 1l- R7- h - ~-o - R6 )n - C
O O O
23~3 where R5 is H, Cl, CH3, or C2H5; R6 is a C2-C6 alkylene; R7 is (CH2)m~
o,m,p ~ , C - C , C = C , / ~C~ , or C = <
H H H CH~ ~l n is 1-4; and m is 0-8.
Monomers typical or this class include, for example, dimethylacrylate of bis(ethyleneglycol) adipate, dimethacrylate of bis(ethyleneglycol) maleate, dimethacrylate oF bis(diethyleneglycol) phthalate, dimethacry-late of bis(tetraethylenglycol) phthalate, dimethylacrylate of bis(tetra-ethyleneglycol) malonate, dimethacrylate of bis(tetraethyleneglycol) sebacate, dimethacrylate of bis(ethylenglycol) phthalate, dime-thacrylate of bisttetraethyleneglycol~ maleate, and the diacrylates and ~-chloro-acrylates curresponding to said dimethacrylates, and the like. The abovecldss of monomers is described in U. S~ Pat. No. 3,457,212 issued July 22, 1969 to Y. Fukuoka et al.
The 3rd class of monomers useful herein are isocyanate-hydroxy-acrylate or isocyanate-aminoacrylate reaction products which may be characterized as acrylate-terminated polyurethanes and polyureides or polyureas. These monomers correspond to the general formula:
r 1l A - X - G - NH - B
_ _ n where X is 0 or N(R5~; R5 is H or a Cl-C7 alkyl; A represents the organic residue of an active-hydrogen-containing acrylate ester wherein the active hydrogen has been removed, the ester being hydroxy- or amino-substituted on the alkyl portion thereof and the methyl, ethyl, and 22~
chlorine homologs thereoF; B is a mono- or polyvalent organic radical selected from the group consisting of alkyl, al~ylene, alkenyl, alkeny-lene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, alkaryl, alkarylene, poly(oxyalkylene), poly(carboalkoxyalkylen~), and heterocyclic radicals both substituted and unsubstituted, and n is 1-6.
Monomers typical of this class include for example, the reaction product of a mono- or polyisocyanate, (e.g., toluene diisocyanate or methylene bis-phenyl diisocyanate) with an acrylate ester containing a hydroxyl or amine group in the non-acrylate portion thereo-f, (e.g.
hydroxyethyl methacrylate). The above class of monomers is described in U.S. Pat. No. 3,425,988 issued Feb. 4, 1969 to J. W. ~orman et al.
The 4th class of monomers useful herein correspond to the acrylate diesters of bis-phenol-type compounds. These monomers correspond to the general formula:
CH2 _ C - C ( 0 ~ C - CH2 ~n ~
R8 R10 1 Rll C ~ O ( C~l2 - C ~ O )n C - C - CH2 where R8 j5 CH3, C2H5, COOH, or H; R9 is H, CH3, or C2H5, R10 is H, CH3, or OH; R1l is H, Cl, CH3, or C2H5; and n is 0-8.
Monomers typical of this class include, for example, dimethacrylate and diacrylate esters of 4,4'-bishydroxy-ethoxy-bisphenol A; dimeth-acrylate and diacrylate esters of bis,ohenol A; etc. These monomers are described in Japanese Pat. Publication 70-15,640 of ~. Orite, M. Natsume, and N. Shimada in 1970.
2~3 The 5th class of monomers consists of monofunctional acrylate and methacrylate esters and the hydroxy-, amido-, cyano-, chloro-, and silane-substituted derivatives thereof. Such monomers include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hy-droxypropyl methacrylate, butyl acrylate, n-octyl acrylate, 2-ethyl-hexyl acrylate, decyl methacrylate~ dodecyl me-thacrylate, cyclohexyl methacrylate, t-butyl methacrylate, acrylamide, N-methylolacrylamide, diactone acrylamide, N-t-butyl acrylamide, N-~-octyl acrylamide, N-butyoxyacrylamide, garnma methacryloxypropyl trimethoxysilane, 2-cyano-ethyl acrylate, 3-cyanopropyl acrylate, tetrahydrofurfuryl chloroacry-late, glycidyl acrylate, glycidyl methacrylate, and the like.
The monomers useful herein are seen to be anaerobically curable monomers having one or more polymerizable acrylate or substituted acrylate ester groups as a common, unifying characteristic. The pre-ferred monomers are those in the 1st and 5th classes above described.
In the production of anaerobic curing adhesive compositions charac-terized by exceptionally high bond strength in the resultant cured poly-mer, the particular monomer employed may be chosen so as to contain an alcoholic, carboxylic, or other relatively polar group substituted thereof. Examples of such polar groups in addition to the hydroxyl and carboxyl groups include amino, amido, cyano, mercapto, and halogen polar groups. Monomers containing hydroxyl groups and/or labile hydrogen atoms are preferred. Examples of suitable monomers include hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate7 diacetone acrylamide, 2-cyanoethyl acrylate, 2-chloroethyl acrylate> 2-hydroxy-3-chloropropyl methacrylate, (meth)acrylic acid, itaconic acid, citraconic acid, maleic acid, and the like. The hydroxy-containing monomers are used in amounts from about 5-95%1 preferably 25-50%, and the carboxyl-containing monorners in amounts from about 001-15%, preFerably 0.5-10%, both by weight based on the total composition weight.
For bes-t results in terms of adhesive activity, the monomers are pre-Ferably employed in a purified state. However, the monomers may be com-prised of commercial grades in which inhibitors, stabilizers, other addi-tives or impurities may be present, provided that the activity and/or stability of the adhesive is not reduced to unacceptable levels.
In the preparation of the anaerobic curing compositions herein, it 1n is possible to employ a mixture of acrylate ester monomers. There may also be utilized, in combination therewith, other non-acrylic, ethylen-ically unsaturated copolymerizable comonomers such as unsaturated hydrocarbons, unsaturated esters and ethers, vinyl esters, and the like. Typical optional comonomers include vinyl acetate, rnethyl vinyl ether, methyl vinyl ketone, poly(ethylene maleate), allyl alcohol, allyl aceta-te, 1-octene, styrene, etc. Preferably9 the total optional non-acrylic monomer(s) will constitute no more than 50% by weight of the monomeric composi-tion, and most preferably no more than 30%.
The anaerobic compositions herein are prepared using conventional techniques. Useful free radical initiators include hydrogen peroxide and peroxy compounds such as organic hydroperoxides (e.g. cumene, t~butyl, and methylethyl ketone hydroperoxides), peroxides (e~g.
benzoyl, cyclohexyl, and hydroxycyclohexyl peroxides), and peresters (e.g. t-butyl perbenzoate and t-butyl peracetate; diazosulfones together with o-benzoic sulfimide (saccharin); c~-amino sulfones (e.g. N-(o- or p-carboethoxyphenyl)-(p-tolylsulfonemethyl) arnine); or azo compounds (e.g. 2,2'-azobis(isobutyronitrile).
Alternatively, an accelera-tor system consis-ting of a N-subs~ituted sulfonamide (e.g. N-tosyl-p-toluene sulfonamide, N-mesyl-p-toluene sul-fonamide9 N-mesyl-benzene sulfonamide, N-mesyl-methane sulfonamide, or N-benzene sulfonamide) or of an organic cyclic sulfimide (e.g. o-benzoic sulfimide) together ~ith an aromatic tertiary amine (e.g~ N,N-dimethyl-p-toluidine, N,N-diethyl-p-toluidine, N,N dimethyaniline, or 3,~-dimethyl-N,N-dimethylaniline) may be used with composi-tions containing at least 25 ppm of active oxygen (see U5s~ Patc No. 4,215,209 issued Jul. 29, 19~0 to D~ K. Ray-Chaudhuri et al. and U.S. Pat. No.
4,235,986 issued November 25, 1980 to W. J. Catena).
In order to improve the storage stability of the composition3 it is preferable, but not necessary, that the composition contain a stabilizer such as an inhibitor of free radical polymerization. Suit-able inhibitors include those conventionally employed, such as hydro-quinones, benzoquinone, naphthoqinone, p-t-butyl catechol, pheno-thiazine, sterically hindered phenols, etc. The amount of inhibitor employed depends9 for example, on the type of monomer used, as well as the free radical initiator used. Generally, it ranges fro~ 0.0001 to 0.1% by weight, based on monomer, preferably 0.0025 to 0.0S%. While the monomer will normally be obtained with a certain amount oF inhib-itor present therein, additional inhibitor may be added as necessary at any time to bring the amount up to the required level. In the case where the monomer is subjected to elevated temperatures, the required amount of inhibitor should be present prior to heating of the mixture.
The presence of a chelating agent (chelator) is also preferable, but not necessary, and it provides the compositions herein with better stability. The chelator is defined, herein, as a compound capable of complexing with a metal atom khrough coordination bonds be-tween the metal and the 1igand atoms of the chelator to form d hetereocyclic ring. Although many chelating agents are suitable, the preferred chelators are oxalic acid and those compounds having a combination of oxygen and nitrogen ligand atoms such as hydroxyquinoline and the ~C -and ~-aminocarboxylates such as tetrasodium ethylenediamine tetracetic acid (Na4ETDA). In general, the chelator useful herein should prefer-ably be soluble in the monomer.
An example of a type of chelator which is not useful herein is the class where all ligand atoms are nitrogen, for examDle, dipyridyl (see U.S. Pat. ~o. 4,038,475 issued July 26, 1977 to E. Freunglass e-t al).
The amount of chelator employed depends mainly on the type of chelator, but also to a nlinor extent on the amounts and types oF other ingredients in the composition. Amounts from 0.0001% to 0.1% by weight of the total composition may be employed, depending upon the particular chelator added. It is noted that with certain chelators, the amount thereof must not exceed 0.01% by weight to obtain an adhesive having good properties. When these chelators are added in amounts above this limit, the bond strength of the adhesive decreases dramatically. The practitioner will readily discover which chelators may be added in 2U which amounts to best advantage. The lower limit of chelator is de-ter-mined by the minimum stability desired in the composition. Preferred amounts of chelator range from 0.001 to 0.02% by weight.
Since the initiator, inhibitor, and chelator employed herein are generally very soluble in the acrylate- and methacrylate-based monomers, it is usually unnecessary to employ a solvent or diluent in order to produce a satisfactory anaerobic composition. If, however, the presence of a solvent is desired3 then any solvent or diluent which dissolves the initiator, inhibitor, and chelator, as well as any accelerators which may be present and are soluble in the monomer, may be emp10yed.
Common solvents are described in the literature and include, for ex-ample, alkanols such as methanol, ethanol and butanol, ketones, substi-tuted and unsubstituted formamides such as formamide and N,N-dimethyl formamide~ and polyester diluents.
One additive which may be employed for purposes of increasing the stability of composi-tions containing the accelerator system based on sulfonamide and an aromatic tertiary amine is an aliphatic tertiary amine, such as trialkylamine wherein each alkyl group contains 1-~
carbon atonns and may have hydroxyl substitution. Suitable such aminesare, for example9 trimethylalnine, triethylamine, diethylpropylamine, tripropylamine, tri-iso-propylamine~ tri-n-butylamine, tri-iso-butylamine, tri~t-butylamine, triethanolamine, ethyldimethylamine, and 2-diethylaminoethanol. Such aliphatic amines, if added, must be pre-sent in amounts not exceeding the molar concentration of the sulfonamidein the monomeric composit~on. If a stoichiometric excess of these amines is present, a suitable adhesive composition will not be obtained.
It is to be understood that these aliphatic amines cannot be used as substitutes for the aromatic teritiary amines required herein, as the former alone will not provide the needed activity for the adhesive.
They are therefore employed only in conjunction with the aromatic amines.
In the production of the novel anaerobic curing compositions herein i~
may also be desirable to employ conventional antioxidants to prolong the shelf life of the composition further. In par'cicular, it may be prefer-red to add a sterically hindered phenol, e.g. butylated hydroxytoluene(BHT), butylated hydroxyanisole ~3HA), or such antioxidants as are com-mercially available under the registered trademarks IONOX 220 (Shell), SANTONOX R (Monsanto), IRGANOX 1010, and I~GANOX 1076 (Ciba-Geigy).
3~3 The composi-tions of this invention may also incorpora-te, as auxiliary accelerators of polymerization, organic acidsJ preferably organic mono-carboxylic acids such as benzoic acid, paratoluic acid or naphthyl acetic acid, or their corresponding anhydrides. Anhydrides of dibasic aromatic acids, such as phthalic or terephthalic acid, may also be used. Ali-phatic acids, are, in general, less satisfactory as accelerators for the compositions herein when the compositions are employed on many nonfer-rous metal surfaces. However, these acids have some utility when the compositions are ernployed on ferrous metals and may conveniently be em-ployed in conjunction with aromatic acids for bonding non-ferrous sur-faces.
There may also be present in the compositions plasticizers such as, for example, dibutyl or diocty1 phthalates, triethylene glycol, or poly-ethylene glycol dilaurate. Tackifying resins, such as styreneJalpha-methylstyrene copolymer (trademark Kristalex of Hercules), and inorganicthickeners are not usually needed, bu-t may be included if desired.
Other optional ingredients include adhesive agents, and cut-glass fibers, as well as visible dyes or ultraviolet fluorescent dyes and/or fluores-cent agents. The dyes serve to increase the visibility of the norrnally colorless or very pale compositions so tha-t treated surfaces can be readily distiniguished from untreated surfaces. Typical dyes include those of -the anthraquinone series such as 1,4-dimonomethylaminoanthra-quinone. Dyestuffs containing unsubstituted hydroxyl groups or unsub-stituted amino groups are in general to be avoided, since they exert a marked inhibiting influence on the polymerization of the compositions.
Depending on the par~icular ingredients and the temperature and time allowed for heating and/or stirring, the composition herein may be stored at room temperature for periods of months and in sorne cases even years prior ~o actual use withollt any evidence oF gelling. It is only necessary that there by present a moderate arnount of air or oxygen which is provided conveniently by a small volume of air in a properly shaped container, preferably made of polyethylene or a similar material which is permeable to air. However, upon exclusion from air by place-ment between adjacent surfaces, the composition will rapidly polymeri7e to form a strong bond, which polymeriza-tion can be further accelerated by use of elevated temperatures, although use of eleva-ted temperatures is not necessary since these compositions produce strong bonds within a mat-ter of minutes.
The anaerobic polymerization of the compositions herein is accel-erated by the surface of certain metals including iron, mild s-teel~
cadmium, cobalt and manganese. Certain other me-tals, including aluminum and zinc have a lower catalytic activity. Non-metallic surfaces such as glass do not catalyze polyrnerization. In the bond-ing of surfaces of low catalytic acti~ity, it may be advantageous to use a primer such as an aldehyde-amine condensate (e.g., those primers represented in U.S. Pat. No. 3,616,040 issued Oct. 26, 1971 to A. S.
Toback) or a derivative of a catalyst metal such as ferric chloride, cobalt naphthanate or manganese resinate.
The reactive thickener may be added at any time during the formu-lation of the anaerobic composi-tion. Preferably it is added ini-tially together with the (meth)acrylate monomers. It is used in amounts from about 5-95% by weight, based on the total composition weight. The preferred amount is 40-80,~.
The following test procedures were employed in the examples below:
Determination of Active ~xygen Content About 0.1 to 0.5 9. of the sample is weighed in a small glass flask ~2~
to which is added 10 ml. glacial acetic acid. A pellet of dry ice about the size of a large pea is placed in the solution to dispel air.
When one-half of the dry ice has evaporated, 1 ml. of a saturated aqueous solution of potassium iodide is added and the flask s~irled to dissolve -the ingredients. A loosely fitting cork is placed in the flask to retain the inert atmosphere and the mixture is heated for 15 minutes in a 60C. ovenO Immediately after removal of the flask from the oven, 10 ml. of water is added to prevent interference of air.
The warm solution is promptly titrated with 0.1 N sodium thiosulfate until the color of the iodine just disappears. Starch indicator should not be added. The active oxygen content is obtained using the formula:
(ml. oF 0.1N Na S 0 ) x (0.08 x 104) wei' ~ amp'le ' = ppm. of active oxygen Determination of Shelf Stabi'lity (Gel Time) A 5 cc. sample of the composition is added to a test tube, which is then placed in a bath heated to 82C. for a minimum of 30 minutes.
As an approximate correlation between oven-aging and aging at room temperature, it is believed that a sample still free from gelling after more than 24 hours of aging will be stable at ambient temperatures in the presence of oxygen for at least about one year.
Determination of Break Torque and Average Prevailing Torque The strength of the bond between threaded members is determined as follows. Two or three drops of each composition are placed on the exposed threads of separate 3/8 x 24 rnild steel Class Il fit bolts (degreased), and immediately thereafter a nut (degreased) with mating threads is run onto the bolt so that the nut is directly in the thread area of the applied composition. The sealant is allowed to set and cure at room temperature for a speci-Fied period of time, normally 0.5, ~32~
1 or 24 hours, and the strength of the bond formed bet~een the nut and bol-t is then measured. The break torque ~or the bond is the amount of torque required for a wrench to remove -the nut on the threads initially.
The average prevailing torque for the bond is the average amount of torque required for a wrench to -turn a series of -three bolts for 1/4 turn 1/2 turn, 3/4 turn and a full turn. Commercially, a bolt sealan-t devel-oping an average torque of 12 inch-pounds aFter 24 hours of cure is considered satisfactory.
Determination of the Tensile Shear and Imoact Stren~th _ These strength properties in the adhesive were determined according to -the ASTM Standard Method of Test Designation D 950-72 (1973) for the impact strength and D 1002-72 (1973) for the tensile shear s-trength.
In the following examples, all parts and percentages are given by weight and all temperatures in degrees Celsius unless o-therwise noted.
EXA~PLE I
This example describes the preparation of a novel reactive thicken-er containing a polymerizable polymeric adduct of an ethyl acrylate/-maleic anhydride copolymer and hydroxyethyl methacrylate dissolved in excess hydroxyethyl methacrylate.
A total of 200 parts ethyl acetate, 30 parts (0.3 mole) ethyl acrylate, 2.16 parts (0.022 mole) maleic anhydride, and 0.3 part azoiso butylnitrile was charged to a 1 l. round bottorn f'las~ fitted with a stirrer, condenser, thermometer, nitroyen inlet adapter9 and addi-tion funnels. The mixture was heated under a nitrogen atrnosphere with stir-ring to 75-80C and held for 30 min. At the end of -the holding period, polymerization had initiated as shown by an increase in the mixture's viscosity. A monomer mixture of 26U parts ethy'l acrylate (2.6 moles) and 2.16 parts maleic anhydride (0.022 mole) and an initiator solution - 2l -of 2.7 parts azoisobutylni-trile in 50 parts e-thyl acetate were added separately and slowly to the initial charge over a 3 hr. period while maintaining the reaction temperature at 75-80C. After completing the addi-tion, the mixture was held for 2 hr. The ethyl acetate was distilled off at atmospheric pressure. A vacuum was then applied to strip off any residual ethyl acetate and any unreacted monomers; the vacuum was maintained For 2 hr. at 110-120~C, broken, and the temper-ature was lowered to 90-100C.
A total of 145 parts (1.12 moles) hydroxyethyl methacrylate and 0.03 part hydroquinone were then aded to the resulting ethyl acryla-te/
maleic anhydride copolymer (98.5/1.5 mole b). The mixture was stirred and maintained at 90-100C for a time sufficient to insure reaction of the anhydride groups in the copolymer with the hydroxyethyl meth-acrylate monomer. The IR absorption of the mixture (a reading of 1780 cm.~1 corresponds to the anhydride group in the polymer) was monitored every 3~ min. After the anhydride groups were completely reacted, the mixture was discharged to a 1 l~ polyethylene bot-tle. The resulting reactive thickener (I-A) contained 67% oF the polymerizable polymeric adduct and 33% hydroxyethyl methacrylate dS diluent, the per-centages being by weight. It had a RF~ Brookfield viscosity of 305,000 cps. at 25C.
EXAMPLE II
This example describes the composition of additional reac-tive thickeners prepared using the method of Example I with some variations in the amount of initiator used. The monomers used include methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), octyl acry-late (OA), methyl methacrylate (MMA), styrene (ST), maleic anhydride (MAN), citraconic anhydride (CAN), hydroxyethyl methacrylate (HEMA), and hydroxypropyl methacrylate (HPMA). The molar composition of the polymer, the excess monomer used in the preparation of -the adduct, and the solids content and viscosity of the reactive thickeners are given in Table I.
EXAMPLE III
This example describes the preparation of anaerobic adhesive for-mulations prepared using the reactive thickener of Exarnple I and some of the reactive thickeners of Example II, The adhesives were evaluated using the testing procedures previously described. Both surfaces were primed with a sulfone primer.
A total of 53.3 parts of the reactive thickener I-A (see Example I) was added to a 500 ml. high density polyethylene beaker, and 10 parts isobsrnyl meth3crylate and 27.0 parts hydroxyethyl methacryla-te were added with stirring. The temperature was raised to 75-30C. The mixture was maintained at this temperature for 2 hr., and then 0.0125 part oxalic acid, 0.005 parts of tetrasodium salt of ethylenediamine tetraamine (Na4EDTA) dissolved in methanol-water (5% solution) were added. The temperature was lowered to 60-65C and 2.5 parts N-mesyl-p-toluene sufonamide were added. The mixture was held for 1 hr., and 0.6 parts N,N-dimethyl toluidine were added slowly in increments of 0.2 part every 30 min. The mixture was held for 1 hr. after the addition was completed; then 6.0 parts methacrylic acid were added. The mixture was held for 45 min. and O.OOS part 2-methoxy-1,4-naphthoquinone ~las added. The mixture was held for 14 min. and 0.5 parts cumene hydro-peroxide were added. The resulting anaerobic adhesive formulation was cooled to room temperature and dischar~ed to a 500 ml. polyethylene bottle.
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EXAMPLE IV
This example describes the preparation oF additional anaerobic ad-hesive formulations using other reactive thickeners (see Example II for the preparation of the thickeners).
Formulation IV-A was prepared by charging 57.4 parts of the reactive thickener designated II-E3, EA/BA/MAN (7605/20/3.5) and HEMA, 33.8 parts hydroxyethyl methacrylate (HEMA), 0.01 part tetrasodium salt of ethylenediamine tetramine (Na4 EDTA), and 2.5 parts N-mesyl-p-toluere sulfonamide to a polyethylene crock ~itted with a stirrer. The mixture was heated to 65-70C over a 45 min. period with stirring. A total of 0.55 part N,N-dimethyl-p-toludine was added in two equal portions with a 1 hr. interval bet~een additionsO The mixture was stirred for about 16 hr. at 65-70C. The active oxygen content and gel time were deter-mined. When the active oxygen content was over 200 p,p.m. and ~he gel time was over 40 min., the mixture was cooled to room temperature. A
total o~F 6.0 parts methacrylic acid (MA) and 0.005 part 2-methoxy-1,4-naphthoquinone were then added, and the mixture was stirred For 1 hr~
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acid, and 1.5 part saccharin tv a polyethylene crock fitt~d with a stir-rer. The mixture was heated to 65-70C over a 30 min. period and then held for 2 hr. with stirring. It was cooled to room temperature, 3.0 parts cumene hydroperoxide were added5 and the mixture was maintained overnight at room temperature with stirring. The gel time at 82C was checked, and when the gel time was over 75 min.? 0~3% (based on total weight of the mixture) N,N-dimethyl-p-toluidine was added. The mixture was heated for about 24 hr. at 65-70C. The gel -time at 82C was again checked and when it was about 25 min.3 50 pOp.m. 1,4-naphthoquinone was added. The mixture was then cooled to room temperature.
Formulation I~-C was prepared by charging 75.0 parts of the reactive thickener designated Il-G, MMA/OA/MAN (37/60/3) and HPMA, 15.53 parts HEMA, 0.01 part Na4 EDTA~ 0.005 part oxalic acid, and 2.0 parts sac-charin to a polyethylene crock fitted with a stirrer. The mixture was heated to 65-70C over a period of 45 nlin. A total of 0.75 part N,N-dimethyl-p-toluidine was added in two equal protions with an interval of 1 hr. between additions. Mixins was con~inued at 65-70C for 2 hr., 6.0 parts methacrylic acid were added, and the mixture was stirred for 1 hr. Then 0.5 part 2-methoxy-1,4-naphthoquinone was added, and stirring was conkinued for about 30 min. The mixture was cooled to room temperature, 0.5 part cumene hydroperoxide was added, and the mixture was maintained at room temperature overniyht with stirringO
The gel time was determined and when it reached 60-70 min. at 82C, stirring was discontinued.
Formulation IV-D was prepared in the same manner as IV-C using 75.2 parts of the reactive thickener designated II-B, EA/CAN (75/25) and HEMA, 15.5 parts HEMA, 0.05 part oxalic acid, 0.005 part 2-methoxy-1, 4-naphthoquinone, and the same arnounts of Na4 EDTA, saccharin, N,N-diemthyl-p-toluidine, methacrylic acid, and cumene hydroperoxide.
The formulations were evaluated as adhesives. The results are given in Table Ill. The testing me-thods previously described ~ere used.
Summari~ing, the present invention provides novel improved anaerobic adhesives containing a novel reac-tive thickener which com-prises a polymerizable polymeric adduct having pendant double bonds dissolved in a reactive monomeric diluent. It also provides a process for preparing the reactive thickener.
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In order to improve the storage stability of the composition3 it is preferable, but not necessary, that the composition contain a stabilizer such as an inhibitor of free radical polymerization. Suit-able inhibitors include those conventionally employed, such as hydro-quinones, benzoquinone, naphthoqinone, p-t-butyl catechol, pheno-thiazine, sterically hindered phenols, etc. The amount of inhibitor employed depends9 for example, on the type of monomer used, as well as the free radical initiator used. Generally, it ranges fro~ 0.0001 to 0.1% by weight, based on monomer, preferably 0.0025 to 0.0S%. While the monomer will normally be obtained with a certain amount oF inhib-itor present therein, additional inhibitor may be added as necessary at any time to bring the amount up to the required level. In the case where the monomer is subjected to elevated temperatures, the required amount of inhibitor should be present prior to heating of the mixture.
The presence of a chelating agent (chelator) is also preferable, but not necessary, and it provides the compositions herein with better stability. The chelator is defined, herein, as a compound capable of complexing with a metal atom khrough coordination bonds be-tween the metal and the 1igand atoms of the chelator to form d hetereocyclic ring. Although many chelating agents are suitable, the preferred chelators are oxalic acid and those compounds having a combination of oxygen and nitrogen ligand atoms such as hydroxyquinoline and the ~C -and ~-aminocarboxylates such as tetrasodium ethylenediamine tetracetic acid (Na4ETDA). In general, the chelator useful herein should prefer-ably be soluble in the monomer.
An example of a type of chelator which is not useful herein is the class where all ligand atoms are nitrogen, for examDle, dipyridyl (see U.S. Pat. ~o. 4,038,475 issued July 26, 1977 to E. Freunglass e-t al).
The amount of chelator employed depends mainly on the type of chelator, but also to a nlinor extent on the amounts and types oF other ingredients in the composition. Amounts from 0.0001% to 0.1% by weight of the total composition may be employed, depending upon the particular chelator added. It is noted that with certain chelators, the amount thereof must not exceed 0.01% by weight to obtain an adhesive having good properties. When these chelators are added in amounts above this limit, the bond strength of the adhesive decreases dramatically. The practitioner will readily discover which chelators may be added in 2U which amounts to best advantage. The lower limit of chelator is de-ter-mined by the minimum stability desired in the composition. Preferred amounts of chelator range from 0.001 to 0.02% by weight.
Since the initiator, inhibitor, and chelator employed herein are generally very soluble in the acrylate- and methacrylate-based monomers, it is usually unnecessary to employ a solvent or diluent in order to produce a satisfactory anaerobic composition. If, however, the presence of a solvent is desired3 then any solvent or diluent which dissolves the initiator, inhibitor, and chelator, as well as any accelerators which may be present and are soluble in the monomer, may be emp10yed.
Common solvents are described in the literature and include, for ex-ample, alkanols such as methanol, ethanol and butanol, ketones, substi-tuted and unsubstituted formamides such as formamide and N,N-dimethyl formamide~ and polyester diluents.
One additive which may be employed for purposes of increasing the stability of composi-tions containing the accelerator system based on sulfonamide and an aromatic tertiary amine is an aliphatic tertiary amine, such as trialkylamine wherein each alkyl group contains 1-~
carbon atonns and may have hydroxyl substitution. Suitable such aminesare, for example9 trimethylalnine, triethylamine, diethylpropylamine, tripropylamine, tri-iso-propylamine~ tri-n-butylamine, tri-iso-butylamine, tri~t-butylamine, triethanolamine, ethyldimethylamine, and 2-diethylaminoethanol. Such aliphatic amines, if added, must be pre-sent in amounts not exceeding the molar concentration of the sulfonamidein the monomeric composit~on. If a stoichiometric excess of these amines is present, a suitable adhesive composition will not be obtained.
It is to be understood that these aliphatic amines cannot be used as substitutes for the aromatic teritiary amines required herein, as the former alone will not provide the needed activity for the adhesive.
They are therefore employed only in conjunction with the aromatic amines.
In the production of the novel anaerobic curing compositions herein i~
may also be desirable to employ conventional antioxidants to prolong the shelf life of the composition further. In par'cicular, it may be prefer-red to add a sterically hindered phenol, e.g. butylated hydroxytoluene(BHT), butylated hydroxyanisole ~3HA), or such antioxidants as are com-mercially available under the registered trademarks IONOX 220 (Shell), SANTONOX R (Monsanto), IRGANOX 1010, and I~GANOX 1076 (Ciba-Geigy).
3~3 The composi-tions of this invention may also incorpora-te, as auxiliary accelerators of polymerization, organic acidsJ preferably organic mono-carboxylic acids such as benzoic acid, paratoluic acid or naphthyl acetic acid, or their corresponding anhydrides. Anhydrides of dibasic aromatic acids, such as phthalic or terephthalic acid, may also be used. Ali-phatic acids, are, in general, less satisfactory as accelerators for the compositions herein when the compositions are employed on many nonfer-rous metal surfaces. However, these acids have some utility when the compositions are ernployed on ferrous metals and may conveniently be em-ployed in conjunction with aromatic acids for bonding non-ferrous sur-faces.
There may also be present in the compositions plasticizers such as, for example, dibutyl or diocty1 phthalates, triethylene glycol, or poly-ethylene glycol dilaurate. Tackifying resins, such as styreneJalpha-methylstyrene copolymer (trademark Kristalex of Hercules), and inorganicthickeners are not usually needed, bu-t may be included if desired.
Other optional ingredients include adhesive agents, and cut-glass fibers, as well as visible dyes or ultraviolet fluorescent dyes and/or fluores-cent agents. The dyes serve to increase the visibility of the norrnally colorless or very pale compositions so tha-t treated surfaces can be readily distiniguished from untreated surfaces. Typical dyes include those of -the anthraquinone series such as 1,4-dimonomethylaminoanthra-quinone. Dyestuffs containing unsubstituted hydroxyl groups or unsub-stituted amino groups are in general to be avoided, since they exert a marked inhibiting influence on the polymerization of the compositions.
Depending on the par~icular ingredients and the temperature and time allowed for heating and/or stirring, the composition herein may be stored at room temperature for periods of months and in sorne cases even years prior ~o actual use withollt any evidence oF gelling. It is only necessary that there by present a moderate arnount of air or oxygen which is provided conveniently by a small volume of air in a properly shaped container, preferably made of polyethylene or a similar material which is permeable to air. However, upon exclusion from air by place-ment between adjacent surfaces, the composition will rapidly polymeri7e to form a strong bond, which polymeriza-tion can be further accelerated by use of elevated temperatures, although use of eleva-ted temperatures is not necessary since these compositions produce strong bonds within a mat-ter of minutes.
The anaerobic polymerization of the compositions herein is accel-erated by the surface of certain metals including iron, mild s-teel~
cadmium, cobalt and manganese. Certain other me-tals, including aluminum and zinc have a lower catalytic activity. Non-metallic surfaces such as glass do not catalyze polyrnerization. In the bond-ing of surfaces of low catalytic acti~ity, it may be advantageous to use a primer such as an aldehyde-amine condensate (e.g., those primers represented in U.S. Pat. No. 3,616,040 issued Oct. 26, 1971 to A. S.
Toback) or a derivative of a catalyst metal such as ferric chloride, cobalt naphthanate or manganese resinate.
The reactive thickener may be added at any time during the formu-lation of the anaerobic composi-tion. Preferably it is added ini-tially together with the (meth)acrylate monomers. It is used in amounts from about 5-95% by weight, based on the total composition weight. The preferred amount is 40-80,~.
The following test procedures were employed in the examples below:
Determination of Active ~xygen Content About 0.1 to 0.5 9. of the sample is weighed in a small glass flask ~2~
to which is added 10 ml. glacial acetic acid. A pellet of dry ice about the size of a large pea is placed in the solution to dispel air.
When one-half of the dry ice has evaporated, 1 ml. of a saturated aqueous solution of potassium iodide is added and the flask s~irled to dissolve -the ingredients. A loosely fitting cork is placed in the flask to retain the inert atmosphere and the mixture is heated for 15 minutes in a 60C. ovenO Immediately after removal of the flask from the oven, 10 ml. of water is added to prevent interference of air.
The warm solution is promptly titrated with 0.1 N sodium thiosulfate until the color of the iodine just disappears. Starch indicator should not be added. The active oxygen content is obtained using the formula:
(ml. oF 0.1N Na S 0 ) x (0.08 x 104) wei' ~ amp'le ' = ppm. of active oxygen Determination of Shelf Stabi'lity (Gel Time) A 5 cc. sample of the composition is added to a test tube, which is then placed in a bath heated to 82C. for a minimum of 30 minutes.
As an approximate correlation between oven-aging and aging at room temperature, it is believed that a sample still free from gelling after more than 24 hours of aging will be stable at ambient temperatures in the presence of oxygen for at least about one year.
Determination of Break Torque and Average Prevailing Torque The strength of the bond between threaded members is determined as follows. Two or three drops of each composition are placed on the exposed threads of separate 3/8 x 24 rnild steel Class Il fit bolts (degreased), and immediately thereafter a nut (degreased) with mating threads is run onto the bolt so that the nut is directly in the thread area of the applied composition. The sealant is allowed to set and cure at room temperature for a speci-Fied period of time, normally 0.5, ~32~
1 or 24 hours, and the strength of the bond formed bet~een the nut and bol-t is then measured. The break torque ~or the bond is the amount of torque required for a wrench to remove -the nut on the threads initially.
The average prevailing torque for the bond is the average amount of torque required for a wrench to -turn a series of -three bolts for 1/4 turn 1/2 turn, 3/4 turn and a full turn. Commercially, a bolt sealan-t devel-oping an average torque of 12 inch-pounds aFter 24 hours of cure is considered satisfactory.
Determination of the Tensile Shear and Imoact Stren~th _ These strength properties in the adhesive were determined according to -the ASTM Standard Method of Test Designation D 950-72 (1973) for the impact strength and D 1002-72 (1973) for the tensile shear s-trength.
In the following examples, all parts and percentages are given by weight and all temperatures in degrees Celsius unless o-therwise noted.
EXA~PLE I
This example describes the preparation of a novel reactive thicken-er containing a polymerizable polymeric adduct of an ethyl acrylate/-maleic anhydride copolymer and hydroxyethyl methacrylate dissolved in excess hydroxyethyl methacrylate.
A total of 200 parts ethyl acetate, 30 parts (0.3 mole) ethyl acrylate, 2.16 parts (0.022 mole) maleic anhydride, and 0.3 part azoiso butylnitrile was charged to a 1 l. round bottorn f'las~ fitted with a stirrer, condenser, thermometer, nitroyen inlet adapter9 and addi-tion funnels. The mixture was heated under a nitrogen atrnosphere with stir-ring to 75-80C and held for 30 min. At the end of -the holding period, polymerization had initiated as shown by an increase in the mixture's viscosity. A monomer mixture of 26U parts ethy'l acrylate (2.6 moles) and 2.16 parts maleic anhydride (0.022 mole) and an initiator solution - 2l -of 2.7 parts azoisobutylni-trile in 50 parts e-thyl acetate were added separately and slowly to the initial charge over a 3 hr. period while maintaining the reaction temperature at 75-80C. After completing the addi-tion, the mixture was held for 2 hr. The ethyl acetate was distilled off at atmospheric pressure. A vacuum was then applied to strip off any residual ethyl acetate and any unreacted monomers; the vacuum was maintained For 2 hr. at 110-120~C, broken, and the temper-ature was lowered to 90-100C.
A total of 145 parts (1.12 moles) hydroxyethyl methacrylate and 0.03 part hydroquinone were then aded to the resulting ethyl acryla-te/
maleic anhydride copolymer (98.5/1.5 mole b). The mixture was stirred and maintained at 90-100C for a time sufficient to insure reaction of the anhydride groups in the copolymer with the hydroxyethyl meth-acrylate monomer. The IR absorption of the mixture (a reading of 1780 cm.~1 corresponds to the anhydride group in the polymer) was monitored every 3~ min. After the anhydride groups were completely reacted, the mixture was discharged to a 1 l~ polyethylene bot-tle. The resulting reactive thickener (I-A) contained 67% oF the polymerizable polymeric adduct and 33% hydroxyethyl methacrylate dS diluent, the per-centages being by weight. It had a RF~ Brookfield viscosity of 305,000 cps. at 25C.
EXAMPLE II
This example describes the composition of additional reac-tive thickeners prepared using the method of Example I with some variations in the amount of initiator used. The monomers used include methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), octyl acry-late (OA), methyl methacrylate (MMA), styrene (ST), maleic anhydride (MAN), citraconic anhydride (CAN), hydroxyethyl methacrylate (HEMA), and hydroxypropyl methacrylate (HPMA). The molar composition of the polymer, the excess monomer used in the preparation of -the adduct, and the solids content and viscosity of the reactive thickeners are given in Table I.
EXAMPLE III
This example describes the preparation of anaerobic adhesive for-mulations prepared using the reactive thickener of Exarnple I and some of the reactive thickeners of Example II, The adhesives were evaluated using the testing procedures previously described. Both surfaces were primed with a sulfone primer.
A total of 53.3 parts of the reactive thickener I-A (see Example I) was added to a 500 ml. high density polyethylene beaker, and 10 parts isobsrnyl meth3crylate and 27.0 parts hydroxyethyl methacryla-te were added with stirring. The temperature was raised to 75-30C. The mixture was maintained at this temperature for 2 hr., and then 0.0125 part oxalic acid, 0.005 parts of tetrasodium salt of ethylenediamine tetraamine (Na4EDTA) dissolved in methanol-water (5% solution) were added. The temperature was lowered to 60-65C and 2.5 parts N-mesyl-p-toluene sufonamide were added. The mixture was held for 1 hr., and 0.6 parts N,N-dimethyl toluidine were added slowly in increments of 0.2 part every 30 min. The mixture was held for 1 hr. after the addition was completed; then 6.0 parts methacrylic acid were added. The mixture was held for 45 min. and O.OOS part 2-methoxy-1,4-naphthoquinone ~las added. The mixture was held for 14 min. and 0.5 parts cumene hydro-peroxide were added. The resulting anaerobic adhesive formulation was cooled to room temperature and dischar~ed to a 500 ml. polyethylene bottle.
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cn XL Ec c o ~ o _ ~ a~
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~3 ~ _ ~ al ~ ~ ~~ ~ ~ a~ aJ
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~1 ~! ~ ~ Lo O E c c o a.) a~ s ,.) ' al , , ., ..... _ ~ o ~ E
L ~ ~ ~ ~ ~ ~ CD ~ `D U:~ ~0 N r~ --L c~ V ~n ~ . --~ ~ O ~ cn ct) ~ ) ~ ~ ~J O ~ -- c E s E ~ ~t u~ ~ ~ N E ~ o ~n ~ ¢ ~ ~, ~ > _ 3 o O ~t c~ 0~ ~ C'lz z 2 1_ O ~ L (Ci Q V
C~ ~ C ~ Z Z Z Z Z~ X ~: --~ _ ~ _ v ~, 1~5 ~5!
'-- a.) ~ ~ ~ ¢ ¢ c~ s o C~ D ~ C X
~ E 2 Z ;2: 2~ ¢ C~ ¢S S S ~ E ~ ,_ O L ~ L _ c - - C~ cr, C~ C~ ~ ~ ~ cr. C~ C~ CC C~ ~ o C~ ~ _ ~ O~ ~ ~ ~ cn ~a o ~ c~ ec ~ LL ~ s~
C ~ Cl: ¢ 2~ ¢ CI C ; ¢ a ¢ c~ 5~ ~ ~ ~1: ~C
LLJ Ll~ LLJ LL~ L~ LL~ LL~ L~ LIJ L~ LL) L l ~ ~ Cr) C llJ ~C
3~
- ~4 -Similar formulations were prepared using the indicated reactive thickeners and methacrylate monomers. The procedure used was the same as above except that ~0 p.p.m. oxalic acid were used. In addition, 1 part ethylene glycol dimethacrylate was used and no N,N-dimethyl toluidine was used. The formulations and their evaluation are summarized in Table II. The results show that the tensile shear strength and impact strength of the adhesives containing the reactive thickeners were much higher than the values for -the control containing the non-reactive thickener, i.e. ethyl acrylate polymer (100%).
EXAMPLE IV
This example describes the preparation oF additional anaerobic ad-hesive formulations using other reactive thickeners (see Example II for the preparation of the thickeners).
Formulation IV-A was prepared by charging 57.4 parts of the reactive thickener designated II-E3, EA/BA/MAN (7605/20/3.5) and HEMA, 33.8 parts hydroxyethyl methacrylate (HEMA), 0.01 part tetrasodium salt of ethylenediamine tetramine (Na4 EDTA), and 2.5 parts N-mesyl-p-toluere sulfonamide to a polyethylene crock ~itted with a stirrer. The mixture was heated to 65-70C over a 45 min. period with stirring. A total of 0.55 part N,N-dimethyl-p-toludine was added in two equal portions with a 1 hr. interval bet~een additionsO The mixture was stirred for about 16 hr. at 65-70C. The active oxygen content and gel time were deter-mined. When the active oxygen content was over 200 p,p.m. and ~he gel time was over 40 min., the mixture was cooled to room temperature. A
total o~F 6.0 parts methacrylic acid (MA) and 0.005 part 2-methoxy-1,4-naphthoquinone were then added, and the mixture was stirred For 1 hr~
Formulation IV-B was prepared by charging 70.0 parts of the reactive thickener desiynated Il-H, ST/MAN (75/25) and HEMA, 25.5 par-ts tetra ethylene glycol dimethacylate, 0.01 part Na4 EDTA, 0.005 part oxdlic 2~1 -- :~5 --_r. ~~ 0 ' U~
~ L~ D 00 1 N
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a ~
.
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(~ . C~) ~ O O 1-- (Y) 0~ 0 ~D O (.D
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~ O ~ O I I I I I I I I I I O
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~ ~_ N (~) ~) ~1 (~)t~) ~t') ~ (r) ~) I,-) C`J a) O ~ E
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~ _ > CJ ~ >,>~5 .~ _ ~ ~ ,- X ~
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acid, and 1.5 part saccharin tv a polyethylene crock fitt~d with a stir-rer. The mixture was heated to 65-70C over a 30 min. period and then held for 2 hr. with stirring. It was cooled to room temperature, 3.0 parts cumene hydroperoxide were added5 and the mixture was maintained overnight at room temperature with stirring. The gel time at 82C was checked, and when the gel time was over 75 min.? 0~3% (based on total weight of the mixture) N,N-dimethyl-p-toluidine was added. The mixture was heated for about 24 hr. at 65-70C. The gel -time at 82C was again checked and when it was about 25 min.3 50 pOp.m. 1,4-naphthoquinone was added. The mixture was then cooled to room temperature.
Formulation I~-C was prepared by charging 75.0 parts of the reactive thickener designated Il-G, MMA/OA/MAN (37/60/3) and HPMA, 15.53 parts HEMA, 0.01 part Na4 EDTA~ 0.005 part oxalic acid, and 2.0 parts sac-charin to a polyethylene crock fitted with a stirrer. The mixture was heated to 65-70C over a period of 45 nlin. A total of 0.75 part N,N-dimethyl-p-toluidine was added in two equal protions with an interval of 1 hr. between additions. Mixins was con~inued at 65-70C for 2 hr., 6.0 parts methacrylic acid were added, and the mixture was stirred for 1 hr. Then 0.5 part 2-methoxy-1,4-naphthoquinone was added, and stirring was conkinued for about 30 min. The mixture was cooled to room temperature, 0.5 part cumene hydroperoxide was added, and the mixture was maintained at room temperature overniyht with stirringO
The gel time was determined and when it reached 60-70 min. at 82C, stirring was discontinued.
Formulation IV-D was prepared in the same manner as IV-C using 75.2 parts of the reactive thickener designated II-B, EA/CAN (75/25) and HEMA, 15.5 parts HEMA, 0.05 part oxalic acid, 0.005 part 2-methoxy-1, 4-naphthoquinone, and the same arnounts of Na4 EDTA, saccharin, N,N-diemthyl-p-toluidine, methacrylic acid, and cumene hydroperoxide.
The formulations were evaluated as adhesives. The results are given in Table Ill. The testing me-thods previously described ~ere used.
Summari~ing, the present invention provides novel improved anaerobic adhesives containing a novel reac-tive thickener which com-prises a polymerizable polymeric adduct having pendant double bonds dissolved in a reactive monomeric diluent. It also provides a process for preparing the reactive thickener.
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Claims (8)
IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An anaerobic composition, comprising:
(A) about 5-95% by weight of a polymerizable, anaerobically curable C2-C5 hydroxyalkyl acrylate or methacrylate monomer;
(B) about 5-95% by weight of a polymerizable polymeric adduct hav-ing pendant double bonds as a reactive thickener; the adduct being the addition reaction product of the C2-C5 hydroxyalkyl acrylate or meth-acrylte monomer of (A) and an ahydride-containing polymer derived from about 0.5-50 mole % maleic, citraconic, or itaconic anhydride and about 50-99.5 mole % of a monomer having the formula CH2 = C(R1)X, wherein R1 is H, CH3 or CN, X is a phenyl or COOR group, and R is a halogen substituted or unsubstituted C1-C10 alkyl group or a halogen, alkoxy, or ester substituted or unsubstituted C7-C20 aralkyl group, the ad-duct being free of unreacted anhydride groups;
(C) 0-15% by weight of a carboxyl-containing monomer; and (D) a free radical initiator in sufficient concentration to ini-tiate cure upon the exclusion of oxygen.
(A) about 5-95% by weight of a polymerizable, anaerobically curable C2-C5 hydroxyalkyl acrylate or methacrylate monomer;
(B) about 5-95% by weight of a polymerizable polymeric adduct hav-ing pendant double bonds as a reactive thickener; the adduct being the addition reaction product of the C2-C5 hydroxyalkyl acrylate or meth-acrylte monomer of (A) and an ahydride-containing polymer derived from about 0.5-50 mole % maleic, citraconic, or itaconic anhydride and about 50-99.5 mole % of a monomer having the formula CH2 = C(R1)X, wherein R1 is H, CH3 or CN, X is a phenyl or COOR group, and R is a halogen substituted or unsubstituted C1-C10 alkyl group or a halogen, alkoxy, or ester substituted or unsubstituted C7-C20 aralkyl group, the ad-duct being free of unreacted anhydride groups;
(C) 0-15% by weight of a carboxyl-containing monomer; and (D) a free radical initiator in sufficient concentration to ini-tiate cure upon the exclusion of oxygen.
2. The composition of Claim 1, further comprising an additive for free radical polymerization selected from the group consisting of a stabili-zer, an accelerator, a chelator, and mixtures thereof.
3. The composition of Claim 1, wherein the anaerobically curable monomer of (A) further comprises d monomer selected from the group consisting of (a) monofunctional acrylate and methacrylate esters or the derivatives of the esters selected from the group consisting of amide, cyano, chloro, and silane and (b) polyfunctional acrylate and methacrylate esters having the formula wherein R5 is H, CH3, C2H5, or CH2OC(=O)C(R6)=CH2; R6 is H, Cl, CH3, or C2H5; R7 is H, OH, or O=C(=O)C(R6)=CH2; m is an integer from 1 to 8; n is an integer from 1 to 20; and p is 0 or 1.
4. The composition of Claim 1, wherein (A) is about 25-50% of hydroxy-ethyl methacrylate and (B) is about 50-75% of the reaction product of hydroxyethyl methacrylate and the polymer derived from about 75-98.5%
of a C1-C8 alkyl acrylate or methacrylate or styrene and about 1.5-25%
maleic or citraconic anhydride.
of a C1-C8 alkyl acrylate or methacrylate or styrene and about 1.5-25%
maleic or citraconic anhydride.
5. The composition of Claim 4, wherein (B) is the reaction product of hydroxyethyl methacrylate and the polymer of ethyl acrylate/maleic anhydride (95-98.5/1.5-5%), ethyl acrylate/citraconic anhydride (98.5/
1.5%), ethyl methacrylate/maleic anhydride (96.5/3.5%), ethyl acrylate/
methyl methacrylate/maleic anhydride (86.5-91.5/5-10/3.5%), ethyl acry-late/butyl acrylate/maleic anhydride (56.5-86.5/10-40/3.5%), butyl acrylate/stryrene/maleic anhydride (82/15/3%), or styrene/maleic anhy-dride (75/25%) or is the reaction product of hydroxypropyl methacrylate and the polymer of methyl methacrylate/octyl acrylate/maleic anhydride (37/60/3%).
1.5%), ethyl methacrylate/maleic anhydride (96.5/3.5%), ethyl acrylate/
methyl methacrylate/maleic anhydride (86.5-91.5/5-10/3.5%), ethyl acry-late/butyl acrylate/maleic anhydride (56.5-86.5/10-40/3.5%), butyl acrylate/stryrene/maleic anhydride (82/15/3%), or styrene/maleic anhy-dride (75/25%) or is the reaction product of hydroxypropyl methacrylate and the polymer of methyl methacrylate/octyl acrylate/maleic anhydride (37/60/3%).
6. The composition of Claim 4, wherein (A) is a mixture of about 27%
hydroxyethyl methacrylate and 10% isobornyl methacrylate and (B) is the reaction product of ethyl acrylate/maleic anhydride polymer (98.5/
1.5%) or wherein (A) is a mixture of 20% hydroxyethyl methacrylate and 17% tetraethylene glycol dimethacrylate and (B) is the reaction product of hydroxyethyl methacrylate and styrene/maleic anhydride polymer (75/
25%).
hydroxyethyl methacrylate and 10% isobornyl methacrylate and (B) is the reaction product of ethyl acrylate/maleic anhydride polymer (98.5/
1.5%) or wherein (A) is a mixture of 20% hydroxyethyl methacrylate and 17% tetraethylene glycol dimethacrylate and (B) is the reaction product of hydroxyethyl methacrylate and styrene/maleic anhydride polymer (75/
25%).
7. The composition of Claim 4, wherein (C) is acrylic or methacrylic acid present in an amount of 0.5-10%.
8. The anaerobic composition of Claim 1, prepared by:
(a) polymerizing, in the presence of a solvent and a free radical ini-tiator, the anhydride and the monomer having the formula CH2 = C(R1)X;
(b) stripping off any unreacted monomer and solvent from the anhydride-containing polymer;
(c) reacting the stripped polymer with the C2-C5-hydroxyalkyl acry-late or methacrylate monomer to form the adduct, the hydroxyalkyl (meth)acrylate monomer being used in an excess of the number of moles required to react by addition with the anhydride groups of the polymer, the excess dissolving the adduct and serving as the anderobically cur-able monomer of (A); and (d) adding a free radical initiator in sufficient concentration to initiate cure upon the exclusion of oxygen.
(c) reacting the stripped polymer with the C2-C5-hydroxyalkyl acry-late or methacrylate monomer to form the adduct, the hydroxyalky1 (meth)acrylate monomer being used in an excess of the number of moles required to react by addition with the anhydride groups of the polymer, the excess dissolving the adduct and serving as the anaerobically cur-able monomer of (A); and (d) adding a free radical initiator in sufficient concentration to initiate cure upon the exclusion of oxygen.
(a) polymerizing, in the presence of a solvent and a free radical ini-tiator, the anhydride and the monomer having the formula CH2 = C(R1)X;
(b) stripping off any unreacted monomer and solvent from the anhydride-containing polymer;
(c) reacting the stripped polymer with the C2-C5-hydroxyalkyl acry-late or methacrylate monomer to form the adduct, the hydroxyalkyl (meth)acrylate monomer being used in an excess of the number of moles required to react by addition with the anhydride groups of the polymer, the excess dissolving the adduct and serving as the anderobically cur-able monomer of (A); and (d) adding a free radical initiator in sufficient concentration to initiate cure upon the exclusion of oxygen.
(c) reacting the stripped polymer with the C2-C5-hydroxyalkyl acry-late or methacrylate monomer to form the adduct, the hydroxyalky1 (meth)acrylate monomer being used in an excess of the number of moles required to react by addition with the anhydride groups of the polymer, the excess dissolving the adduct and serving as the anaerobically cur-able monomer of (A); and (d) adding a free radical initiator in sufficient concentration to initiate cure upon the exclusion of oxygen.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US299,390 | 1981-09-04 | ||
| US06/299,390 US4401793A (en) | 1981-09-04 | 1981-09-04 | Polymeric adducts with pendant polymerizable double bonds, their preparation and use as reactive thickeners in improved anaerobic compositions |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1182238A true CA1182238A (en) | 1985-02-05 |
Family
ID=23154582
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000405437A Expired CA1182238A (en) | 1981-09-04 | 1982-06-17 | Anaerobic composition including a hydroxy (meth) acrylate and a polymerizable polymeric adduct with pendant double bonds |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4401793A (en) |
| EP (1) | EP0073890B1 (en) |
| CA (1) | CA1182238A (en) |
| DE (1) | DE3270236D1 (en) |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4745138A (en) * | 1985-08-05 | 1988-05-17 | Pony Industries, Inc. | Radiation curable partial esters of anhydride-containing copolymers |
| US4722947A (en) * | 1985-08-05 | 1988-02-02 | Pony Industries, Inc. | Production of radiation curable partial esters of anhydride-containing copolymers |
| DE3536077A1 (en) * | 1985-10-09 | 1987-04-09 | Muehlbauer Ernst Kg | POLYMERIZABLE ACID AND ACID DERIVATIVES COMPOUNDS, MIXTURES CONTAINING THE SAME AND THEIR USE |
| US5035892A (en) * | 1988-05-09 | 1991-07-30 | Dow Corning Corporation | Antimicrobial superabsorbent compositions and methods |
| US4990338A (en) * | 1988-05-09 | 1991-02-05 | Dow Corning Corporation | Antimicrobial superabsorbent compositions and methods |
| JP2962739B2 (en) * | 1988-07-30 | 1999-10-12 | 日本石油化学株式会社 | Method of forming light-cured coating film |
| US5114830A (en) * | 1988-10-28 | 1992-05-19 | W. R. Grace & Co.-Conn. | Solder mask resins having improved stability containing a multifunctional epoxide and a partial ester or styrene-maleic anhydride copolymer |
| US5683536A (en) * | 1991-03-06 | 1997-11-04 | Loctite Ltd. | Method of bonding PVC |
| DK0502733T3 (en) * | 1991-03-06 | 1997-12-29 | Loctite Ireland Ltd | Air activatable polymerizable compositions |
| IE941002A1 (en) * | 1994-12-22 | 1996-06-26 | Loctite Ireland Ltd | Air-activatable polymerisable compositions containing¹tetrazoles |
| WO1997045543A2 (en) * | 1996-05-28 | 1997-12-04 | The Government Of The United States Of America, As Represented By The Secretary Of Health And Human Services, National Institutes Of Health | Cc chemokine receptor 5, antibodies thereto, transgenic animals |
| US5665828A (en) * | 1996-10-31 | 1997-09-09 | Dow Corning Corporation | Acryl-functional polybutylene |
| EP1023360B1 (en) | 1997-10-16 | 2011-03-09 | Sun Chemical Corporation | PHOTONEUTRALIZATION OF pH SENSITIVE AQUEOUS POLYMERIC DISPERSIONS AND METHODS FOR USING SAME |
| MXPA03001406A (en) | 2000-08-15 | 2004-05-04 | Surmodics Inc | Medicament incorporation matrix. |
| US6719053B2 (en) | 2001-04-30 | 2004-04-13 | Bj Services Company | Ester/monoester copolymer compositions and methods of preparing and using same |
| US7001930B2 (en) * | 2003-01-14 | 2006-02-21 | Dymax Corporation | Acrylic resin formulations curable to clear, heat-resistant bodies |
| US7226959B2 (en) | 2003-11-06 | 2007-06-05 | Sun Chemical Corporation | Water soluble energy curable stereo-crosslinkable ionomer compositions |
| US8598279B2 (en) * | 2007-07-23 | 2013-12-03 | Henkel IP US LLC | Adducts useful as cure components for anaerobic curable compositions |
| EP2398508B1 (en) * | 2009-02-18 | 2016-05-11 | Quick-Med Technologies, Inc. | Superabsorbent materials comprising peroxide |
| FR3030546B1 (en) * | 2014-12-22 | 2018-04-06 | Arkema France | LIQUID (METH) ACRYLIC SYRUP, PROCESS FOR THE IMPREGNATION OF A FIBROUS SUBSTRATE BY THE SAME, AND COMPOSITE MATERIAL OBTAINED AFTER POLYMERIZATION OF THE IMPREGNATION SYRUP |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE761906A (en) * | 1970-01-28 | 1971-07-22 | Du Pont | FILM-FORMING DISPERSIONS |
| US3925330A (en) * | 1974-01-07 | 1975-12-09 | Goodrich Co B F | Castable compositions containing unsaturated liquid vinylidene-terminated polymers |
| US4104241A (en) * | 1974-10-24 | 1978-08-01 | Owens-Corning Fiberglas Corporation | Thermosetting additives for polyester-based molding compounds |
-
1981
- 1981-09-04 US US06/299,390 patent/US4401793A/en not_active Expired - Fee Related
-
1982
- 1982-06-17 CA CA000405437A patent/CA1182238A/en not_active Expired
- 1982-06-29 DE DE8282105796T patent/DE3270236D1/en not_active Expired
- 1982-06-29 EP EP82105796A patent/EP0073890B1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| US4401793A (en) | 1983-08-30 |
| DE3270236D1 (en) | 1986-05-07 |
| EP0073890A1 (en) | 1983-03-16 |
| EP0073890B1 (en) | 1986-04-02 |
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